New trends in the economic systems management in the context of modern global challenges

New trends in the economic systems management in the context of modern global challenges: collective monograph / scientific edited by M. Bezpartochnyi, in 2 Vol. // VUZF University of Finance, Business and Entrepreneurship. – Sofia: VUZF Publishing House “St. Grigorii Bogoslov”, 2020. – Vol. 1. – 309 p

Isoform-Selective and Stereoselective Inhibition of Hypoxia Inducible Factor‑2

Hypoxia inducible factor (HIF) transcription factors reside at the center of signaling pathways used by mammalian cells to sense and respond to low oxygen levels. While essential to maintain oxygen homeostasis, misregulation of HIF protein activity correlates with tumor development and metastasis. To provide artificial routes to target misregulated HIF activity, we identified small molecule antagonists of the HIF-2 transcription factor that bind an internal cavity within the C-terminal PAS domain of the HIF-2α subunit. Here we describe a new class of chiral small molecule ligands that provide the highest affinity binding, the most effective, isoform-selective inhibition of HIF-2 in cells, and trigger the largest protein conformation changes reported to date. The current results further illuminate the molecular mechanism of HIF-2 antagonism and suggest additional routes to develop higher affinity and potency HIF-2 antagonists

Isoform-Selective and Stereoselective Inhibition of Hypoxia Inducible Factor‑2

Hypoxia inducible factor (HIF) transcription factors reside at the center of signaling pathways used by mammalian cells to sense and respond to low oxygen levels. While essential to maintain oxygen homeostasis, misregulation of HIF protein activity correlates with tumor development and metastasis. To provide artificial routes to target misregulated HIF activity, we identified small molecule antagonists of the HIF-2 transcription factor that bind an internal cavity within the C-terminal PAS domain of the HIF-2α subunit. Here we describe a new class of chiral small molecule ligands that provide the highest affinity binding, the most effective, isoform-selective inhibition of HIF-2 in cells, and trigger the largest protein conformation changes reported to date. The current results further illuminate the molecular mechanism of HIF-2 antagonism and suggest additional routes to develop higher affinity and potency HIF-2 antagonists

Synthesis and Biochemical Evaluation of Thiochromanone Thiosemicarbazone Analogues as Inhibitors of Cathepsin L

A series of 36 thiosemicarbazone analogues containing the thiochromanone molecular scaffold functionalized primarily at the C-6 position were prepared by chemical synthesis and evaluated as inhibitors of cathepsins L and B. The most promising inhibitors from this group are selective for cathepsin L and demonstrate IC₅₀ values in the low nanomolar range. In nearly all cases, the thiochromanone sulfide analogues show superior inhibition of cathepsin L as compared to their corresponding thiochromanone sulfone derivatives. Without exception, the compounds evaluated were inactive (IC₅₀ > 10000 nM) against cathepsin B. The most potent inhibitor (IC₅₀ = 46 nM) of cathepsin L proved to be the 6,7-difluoro analogue <b>4</b>. This small library of compounds significantly expands the structure–activity relationship known for small molecule, nonpeptidic inhibitors of cathepsin L

Development of Inhibitors of the PAS‑B Domain of the HIF-2α Transcription Factor

Hypoxia inducible factors (HIFs) are heterodimeric transcription factors induced in a variety of pathophysiological settings, including cancer. We describe the first detailed structure–activity relationship study of small molecules designed to inhibit HIF-2α–ARNT heterodimerization by binding an internal cavity of the HIF-2α PAS-B domain. Through a series of biophysical characterizations of inhibitor–protein interactions (NMR and X-ray crystallography), we have established the structural requirements for artificial inhibitors of the HIF-2α–ARNT PAS-B interaction. These results may serve as a foundation for discovering therapeutic agents that function by a novel mode of action